The hope was given to Naruto by the people, who in turn gave it to the people. Ay and Ohnoki were planning on breaking the alliance after the war, but that changed when the Kage's worked together to fight Madara. They made the promise to Naruto that they'd defeat Madara no matter what, but they had given up on casting away the alliance before Naruto even arrived. Naruto had no say in starting the war, no say in the alliance and no say in the peace that arrived afterwards. He helps to maintain it as his role as the current Hokage. The hope however isn't give by Naruto alone. Asura before him, Hagoromo, heck even Sasuke inspire hope. Nagato and Obito were originally like Naruto and that is why they ended up agreeing with him because they went back to who they used to be.Thank you for using the word hope because when theirs hope theirs peace and hope can be easily lost just like all the villains that naruto faced but when its regained people believe and start to trust one another. only naruto have this ability to give hope. you cant be hokage because you want to be knowledge but because you are knowledge, i think that somewhere in the lines of what itachi said. the kage are just political leaders, naruto is like jesus hes a son of god meant for great things being hokage was just part of the job to equallize his power to the world and to bring peace. the alliance was formed by the agreement of all the kages, 2 out of the five(rikage and the old kage) were planing to **** over the other nations after the war but guess what they didnt know why because of naruto. please make a ban wagon list of vilians that decide that narutos way was the right way because you'll have one hell of a list of crimals. also the sages mistake in the end was entrusting one of his kid all the power, something that itachi did to but was able to correct.
Orochimaru
Madara
Black Zetsu
Kaguya
Momoshiki
Kinshiki
Itachi
Kisame
Deidara
Sasori
Hidan
Kakuzu
Spiral Zetsu
Are just a few that disagreed with Naruto and never altered their view. If anything, it is Naruto who changed his view to agree with Itachi. (When Itachi corrects him on what a Hokage really is.) We have two villains who agree with Naruto and a mass of others that doesn't. You also stated that the mistake Hagoromo did was entrust Asura alone to bring peace. He did however find the solution in the end. To entrust both of them with the mission to find peace, both Naruto and Sasuke.